??? VT Thermostat problem ???

[redtamada]

Hey guys just wandering if anyone can help me with this problem. I have a 98 VT V6 which has new radiator, hoses, radiator cap and water pump and is now on its third thermostat. I have run the car without the thermostat and besides taking a while to warm up it runs at a normal temp of just below half on the temp gauge and does not overheat. However with the thermostat in the car is constantly overheating more so at idle and cooling under load. I am assuming the thermostat is opening late (would be incredibly unlikely as 3 thermostats can't be dodgy), there is air in the system (would air move through the system more freely with the thermostat out and hence not overheat?) or the temp gauge is faulty. I have bled the system already and will try again tonight. The oil is good and does not appear milky. Is it possible that with the old parts the cars ECU somehow changed the cars comfortable operating temp which causes the gauge to react the way it does or is it more likely a fault with something else previously mentioned above? Any advice would be greatly appreciated, cheers.

[don0xer]

bring up your special menu (hold mode and up on startup) and scroll accross till your temp shows, watch it. normally the standard thermostat will open at 95*C and cut off around 88*C iirc and those temps should not make the temp gauge move at all. ive seen my car get to 108-110 around that mark aswell on the gauge in summer. if all else fails, take it to a good mechanic, describe whats happening to them over the phone and if they give u something like 'uhh thats gonna cost $1500 to replace ur radiator' or something stupid hang up :P

[andyman]

is the thermostat installed the correct way, ie the wax pointing downwards?, what temperature is the thermostat, have you tried replacing the temp sensors?, have you bleed the cooling system correctly?

if the car is running at normal temperature without a thermostat, you may have an air-lock

[redtamada]

Cheers Don0xer, just bled it again and used the temp gauge I didn't know existed and she's all sweet. Very much appreciated, headache easing.....